Treatment of cellulose derivatives of products made therewith



' Patented May 19, 1931 PATENT OFFICE RENE CLAVEL, F BASEL-AUGST, NEAR, BASEL, SWITZERLAND TREATMENT OF CELLULOSE DERIVATIVES 0F PRODUCTS MADE THEREWITE No Drawing.

This invention relates to the dyeing (under which term is included dyeing, printing or stencilling operations generally) of artificial filaments, threads, yarns, fabrics, films or other products made from or containing cellulose acetate, hereinafter referred to as celluose acetate goods.

It is known that the affinity of dyestuffs for cellulose acetate can be improved by adding 1 to the dyebath or the printing paste certain organic and inorganic compounds in the form of acids, salts or bases. The substances hitherto employed were such as to modify the surface of the fibre by hydrolysis or by a solvent or similar swelling action, so as to render the surface of the fibre capable of absorbing the dyestuff. Alternatively, substances were used which acted as dispersing agents, the dyestuffs being thus rendered capable of be- 0 m more readily absorbed by the fibre.

fProcesscs for treating cellulose acetate goods to increase their weight and volume, and for other purposes, are described in the U. S. A. patent application of Dr. Camille Dreyfus and Herbert Platt, No. 57 ,956, filed September 22, 1925, and U. S. Patent No. 1,731,298 of October 15, 1929.

Now as the result of much experiment it has been found that by loading cellulose acetat-e goods with tin phosphate or other metallic salt or salts that is or are insoluble in water, and particularly salts that act as loadmg agents for natural silk, the loaded goods display an increased afiinity for dyestuffs colouring matters or colouring compounds,

and can not only be dyed, printed or stencilled with the dyes, colouring matters or colouring compounds ordinarily used for dyeing and similarly treating cellulose acetate, all hereinafter referred to by the generic term dyestuffs, but are also capable of being satisfactorily dyed printed or stencilled with dyestuffs or colouring matters having only a feeble affinity or no aflinity for cellulose acetate, such for example asdyestufis contain- Serial No. 84,764.

ing sulphonic acid groups and the dyestuffs or colouring matters used for cotton goods.

According to this invention, goods made of or containing cellulose acetate are loaded witha metallic salt'or salts that is or are insoluble in water, preferably such as act as loading agents for natural silk, and are afterwards dyed, printed or stencilled with dyestuffs, colouring matters or colouring compounds in any usual or suitable way.

The loading agents may be deposited on the goods by'treatment in succession with a bath containing in solution a salt or salts of a metal or metals such as tin, zinc, tungsten, or aluminium and a bath containing a solution of phosphate, silicate, tannin or other compound or compounds adapted to deposlt the metal .or metals as an insoluble salt or salts upon the goods.

The first bath is preferably maintained at 5 a temperature not lower than 50 C. during the treatment of the goods, but lower temperatures may also be used.

The loading operation may be repeated, it being found that with each successive loading operation the increase in the capacity of the goods for absorbing dyestufis becomes greater and greater.

Cellulose. acetate goods, after they have been loaded in this manner, may be dyed with direct, acid, basic and other dyestuffs.

The process presents a marked advantage over those heretofore in use in that the colouring of the goods is of greater depth and brilliancy.

For instance, using a bath containing 1 per cent. (calculated on the fibre) of Janus black D, Color Index No. 134:, with a cellulose acetate fibre that had been loaded with 30 per cent. of tin phosphate, a deep black was obtained; while with untre"ted fibre a light grey was produced, and with a fibre subjected to superficial hydrolysis there resulted a medium grey. Using rhodamine G Color IrPdex No. 750, under similar conditions, a cellulose acetate fibre loaded with tin phosphate was dyed to a brilliant deep shade, in marked contrast to the paler shade obtained on un- The colours produced in accordance with this invention may readily be discharged, the process thus presenting advantages over those itherto in use.

Ewample 1 kilo. of cellulose acetate yarn in hanks isv worked for 1 hour in a bath containing 90 grams of tin (in the form of stannic chloride) per litre, the bath being maintained at a temperature of 50 C. The yarn is removed from the bath, Washed twice with hard water, and centrifuged. The yarn is now placed in a bath containing 60 grams of disodium phosphate per litre. After treatment in the path for hour at a temperature of 60 C. the yarn is removed and Washed with soft water. The-loaded yarn is then dyed in a bath containing 20 litres of water in which is dissolved 10 gms. of Janus black D, Color Index No. 876, and 60 cc. of acetic acid, the bath being maintained at 60 C. The yarn is left in the bath for hour an is then centrifuged and dried.

Example I] Cellulose acetate fabrics are loaded and 'prepared for printing by treatment in suc 50 grams of Capri blue 25 grams of concentrated acetic acid 325 grams of water 600 grams of a thick gum The printed goods are thoroughly dried and steamed for about hour and finally well washed and dried.

It will be understood that the process is not limited to the procedure set forth in the preceding examples, but may vary widely therefrom without departing from the inven-' tion. The process, moreover, is applicable to the dyeing, printing or stencilling of mixed yarns, fabrics or materialscontaining filaments or yarns of cellulose acetate associated with other fibres or yarns, such as cotton or other cellulose fibres (natural or artificial), Wool, and silk, said mixed yarns, fabrics or materials being likewise included in the term cellulose acetate goods.

- The term loading is employed in this specification in the ordinary technical significance in which it is employed in connection with natural silk, that is to say, to denote the technical operation of increasing the weight of the material under treatment; it does not include the production of such relatively small increases in weight as may be associated with processes of dyeing, such for example, as those effected with the aid of mordants.

What I claim and desire to secure by Letters Patent is:

1. A process of dyeing cellulose acetate materials which comprises loading said materials by forming therein a water insoluble metallic salt and thereafter dyeing the loaded materials with a dyestufli' that has but little affinity for unloaded cellulose acetate material.

2. A process of dyeing cellulose acetate materials which comprises loading said materials by an operation comprising two stages, the first consisting in swelling and impregnating the materials with a solution of a salt of a loading metal, and the second consisting in treating the materials with a solution of a compound adapted to fix the-metal therein as an insoluble salt, and thereafter dyeing the loaded materials with a dyestuif that has but little afiinity for unloaded cellulose acetate material.

3. A process of dyeing cellulose acetate materials which comprises loading said materials by swelling and impregnating them with a solution of a salt of tin and then treating them with a solution of a compound adapted to fix the tin therein as an insoluble salt, and thereafter dyeing the loaded materials with a dyestuif that has but little affinity for unloaded cellulose acetate material.

4.. A process of dyeing cellulose acetate materials which comprises loading said materials by swelling and impregnating them with a solution of stannic chloride and then treating them with a solution of a compound adapted to fix the tin therein as phosphate of tin, and thereafter dyeing the loaded materials in any suitable manner.

5. A process of dyeing cellulose acetate materials which comprises loading said materials by swelling and impregnating them with a solution of a salt of a loading metal and then treating them with a solution of a compound adapted to fix the metal therein as an insoluble phosphate, and thereafter dyeing the loaded materials in any suitable manner. 1

6. A process of dyeing cellulose acetate materials which comprises loading said materials by swelling and impregnating them terials which comprises loading said materials by first swelling and impregnating them with a heated solution of a chloride of a loading metal and then treating them with a solution of a compound adapted to fix the metal therein as an insoluble salt, and there after dyeing the loaded materials with a dyestufl that has but little aflinity for unloaded cellulose acetate material.

8. A process of dyeing cellulose acetate materials which comprises loading said materials by first swelling and impregnating them with a solution of a chloride of a loading metal at a temperature of about 0., and then treating them ,with a solution of a compound adapted to fix the'metal therein as an insoluble salt, and thereafter dyeing the loaded materials with a dyestufi that has but little afiinity for unloaded cellulose acetate material.

9. A process of dyeing cellulose acetate materials which comprises loading said no.-

terials by first treating them with a heated solution of stannic chloride and then treating them with a solution of a compound adapted to fix the tin therein as an insoluble salt, and thereafter dyeing, the loaded materials with a dyestufl that has but little aflinity for unloaded cellulose acetate material.

10. A process of dyeing cellulose acetate materials which comprises loading said materials by first treating them with a solution of stanmc chloride at a temperature of about 50 0., and then treating them with a solution of a compound adapted to fix the tin therein as an insoluble salt, and thereafter dyeing the loaded materials' with a dyestufi that has but little aflinity for unloaded cellulose acetate material.

11. A process of dyeing cellulose acetate materials which comprises loading said materials by swelling and impregnating them with a solution of stannicchloride and then treating them with a solution of acompound adapted to fix the tin therein as an insoluble salt, and thereafter dyeing the loaded materials with a dyestufi that has but little affinity for unloaded cellulose acetate mate rial.

12. As a new article of manufacture, a material comprising cellulose acetate loaded with a water-insoluble metal salt, and a d estulf that has but little aflinity for unloa ed cellulose acetate yarn.

13. As a new article of manufacture, a material comprising cellulose acetate loaded with a water-insoluble tin salt, and a dyeyarn.

stuif that has but little aflinity for unloaded cellulose acetate yarn.

14. As a new article of manufacture terial containing filaments comprising cellulose acetate, and a dyestufl that has but little aflinity for unloaded cellulose acetate yarn.

15. As a new article of manufacture, a material containing filaments comprising cellulose acetate loaded with a water-insoluble metal salt, and a dyestuff that has but little a maloaded affinity for unloaded cellulose acetate yarn.

16. Asa new article of manufacture, a

fabric containing filaments comprising cellulose acetate loaded with a water-insoluble metallic salt, said fabric having a pattern thereon printed with a dyestufi having but little aflinity for unloaded cellulose acetate 17. A fabric containing loaded cellulose acetate yarn dyed with a dyestuff thathas but little aflinity for unloaded cellulose acetate yarn. I i In testimony whereof I have hereunto subscribed my name.

- RENE GLAVEL; 

